You don't need to purchase copyright removal key for 'localhost'. It doesn't make any sense. You need to purchase it for live (published) site in case you want to remove "powered by nopCommerce" notice. Let me know your live site URL, and I'll update your order details with this URL.
Not sure that I got you. Please post your live site URL here and I'll update your order details.
We don't send license keys. You have to manually remove all copyright notices. Just edit the NopCommerceStore\Modules\Footer.ascx control and recompile the solution.